Modules for through- and under-drawing flooring

ABSTRACT

Grid-like plastic apertured square modules, removably laid on a normal concrete floor as a through-draining and under-draining flooring structure, each have a multiplicity of dependent like legs, and, along two adjacent sides, have integral marginal depressed apertured lugs projecting laterally for receiving like feet of neighboring modules; and each lug has a pair of upward projections so spaced and shaped that perpendicular lug-aligned and -transverse grid bar portions adjacent a lug-received foot of another module are resiliently gripped, received respectively between and against the projections. The modules may have certain under-grooving providing at times a cooperative effect with the improved interlock.

iinit ed States Patent [1 1 Spica Mar.4, 1975 1 1 MODULES FOR THROUGH- AND UNDER-DRAWING FLOORING 21 Appl. No.: 458,859

Related [1.8. Application Data [63] Continuation-impart of Ser. No. 280,968, Aug. 16,

1973, Pat, N0. 3,802,144.

[52] U.S. Cl 52/100, 52/591, 52/177, 404/36, 404/41 [51] Int. Cl. E04c 2/10, E04c 1/30 [58] Field of Search 46/25, 30, 31; 52/592, 52/591, 594, 98, 100; 404/35, 36, 41

[56] References Cited UNITED STATES PATENTS 2,353,398 7/1944 Greulich 404/36 2,655,525 9/1953 McGuirem. 404/35 2,680,698 6/1954 Schnee 404/35 2,776,521 l/1957 Zimmerman 1 46/30 2,791,868 5/1957 Viken 46/30 2.902.821 9/1959 Kelly 46/30 2,999,431 Mitchell 52/594 3,274,727 9/1966 Zander 46/31 3,285,464 11/1966 Boydman 46/31 3,522,137 7/1970 De la Rive BOX 46/31 3,708,381 1/1973 Schwartz 52/592 Primary Examiner-Frank L. Abbott Assistant Examiner-Henry Raduazo Attorney, Agent, or FirnzP. D. Golrick [57] ABSTRACT Grid-like plastic apertured square modules, removably laid on a normal concrete floor as a through-draining and under-draining flooring structure, each have a multiplicity of dependent like legs, and, along two adjacent sides, have integral marginal depressed apertured lugs projecting laterally for receiving like feet of neighboring modules; and each lug has a pair of upward projections so spaced and shaped that perpendicular lug-aligned and -transverse grid bar portions adjacent a lug-received foot of another module are resiliently gripped, received respectively between and against the projections The modules may have certain undergrooving providing at times a cooperative effect with the improved interlock.

10 Claims, 5 Drawing Figures MODULES FOR THROUGH- AND UNDER-DRAWING FLOORING This application is a continuation-in-part of my allowed application Ser. No. 280,968, filed Aug. 16, 1973, now US. Pat. No. 3,802,144.

The present invention represents an improvement upon the modular structure and modular array of the above identified application, which disclosed, as principal structural elements, tile-like molded plastic modules of generally square form, presenting a grid-like top aspect with integral feet dependent from the grid-bar intersections, whereby a generally flat top floor surface with a large number of drainage apertures is provided and also draining under-flow space; the square primary modules further including, on two preferably adjacent sides, integral lateral lug means projecting at a level below that of the grid bars and adapted interlockingly to receive feet of the other non-lugged sides of similar square modules. The interlock structure however serves to prevent only lateral, i.e., horizontal separation, of the modules. This structure permits quick, ready laying yet easy removal, and by suitable orientation in a flooring array, also interlock with the appropriate disclosed ramp module elements.

Among other particular advantageous aspects, the disclosed modules of that application afford durability, easy molding in thermoplastic or thermosetting plastic, facilitation of cutting in a convenient fashion not interferring with basic function or with interlock, while presenting a good appearance, where for one reason or another modules must be cut, especially where a horizontal dimension of the array is not an integral multiple of the module size.

In the preferred form of those modules, the lateral lugs, apertured to receive feet of an adjacent module, project laterally in alignment with respective module grid bars; the module feet occur at grid bar intersections; and the grid bars have an upwardly convergent trapezoidal cross section.

The present invention offers an improvement on the lug-foot interlock structure of that prior application, by here providing an additional interlock at each lug-foot engagement to prevent a vertical separation of the lug and foot, advantageously assuring maintenance of a smoother top of the modular array, despite unevenness of the underflooring; while also separation is minimized under loading, especially live loading, in unfavorable conditions or installation.

It is the general object of the present invention to provide a module of the character described for through-drainage flooring which has an improved interlock structure.

Another object of the present invention is the provision of an improved interlock in grid-like modules by a simple and comparatively low cost structural expedient.

A still further object is to provide an improved interlocking in primary module structure which is not impaired by cutting of a module to any of incrementally smaller sizes as may be required.

Other objects and advantages will appearfrom the following description and the drawings wherein:

FIG. I is a fragmentary schematic or outline plan view of an array of flooring modules in accordance with the present invention, as laid, for example, in a vehicle garage;

FIG. 2 is a fragmentary plan view of a primary module with a portion of a ramp module interlockingly engaged therewith;

. FIG. 3 is a sectional view taken as indicated by the line 3-3 in FIG. 2;

FIG. 4 is an enlarged fragmentary plan view of an im terlock lug structure; and

FIG. 5 is a vertical section of the lug taken as indicated at 5-5 in FIG. 5.

FIG. 1 of the drawings, illustrating one application of plastic modules embodying the invention, represents in plan outline an array of primary modules P, generally square in their identical full, i.e., as molded, uncut form; the array covering from wall to wall say the concrete floor slab of a typical residential garage, and along the edge at the vehicle floor entrance, the array having a co-operating end-to-end array of special molded ramp modules R.

The primary module may be considered as a flat plate body structure having the through-apertures, the bottom feet, the laterally projecting apertured lugs on two sides and stub projections from the other two sides, as hereinafter named.

It is to be understood that the large squares are intended only to symbolize positions of modules in the array, and that normally in the array appearance the grid pattern is uniform and uninterrupted throughout, the appearance identity of the individual primary modules being lost in or merged into the whole.

As may be seen from FIGS. 2 and 3, the primary square module from above presents the appearance of a grid or grating of perpendicularly intersecting sets of equi-spaced like thick grid bars, designated 11 and 12, defining therebetween apertures ll3 generally square in plan, with the top surface of the bars being flat and coplanar; while on the bottom of the bar intersections, preferably as here shown at all intersections, there are integral dependent, generally cylindrical, equi-spaced support feet 14.

The grid bar vertical cross section is trapezoidal with parallel flat top and bottom surfaces and upwardly convergent tapering like sides, so that the equally but oppositely sloped lateral surfaces define the square openings 13 with opposed sides sloping downwardly convergently. This provides in drainage, cleanliness and other aspects, certain advantages, of which some are noted in the prior application. Rather than being hollow from the bottom ends, as might be desirable in some cases to diminish weight and also save material, the feet preferably are solid for strength and durability.

As seen in FIG. 2, two adjacent sides (each at time referred to as a straight edge or side, or a bar side) of a module P are defined by a bar 11 and a bar 12 respectively, from each of which project like apertured interlock lugs 15 at a location downwardly offset so that their top surfaces occur at the level of or slightly below the plane of the bottom surface of the bars, to permit overlapping by an adjacent module for interlocking. As seen in plan view the lugs 15 occur in alignment with respective alternate bars 11 or 12, with the effective axes or centers of their foot-receiving interlock apertures 16 being respectivelyspaced from the centers of the proximate feet 14, from the top regions of which they extend, by a distance equal to the spacing between adjacent feet. Since the feet are present at all bar intersections, at least on the outermost bars, and the lugs occur in alignment with bars, the bars having like equi-spacing in both sets, lugs are appropriately located to receive feet of adjacent modules for the possible mutual orientations, without further specifications on placement along the edges. A shallow groove may be provided at 17 along the projecting lugs so that they may be easily broken off or offer a guide for sawing if desired, thereby readily to provide a smooth edge, for example at a wall adjacent edge of an array.

Along the other remaining two sides of the module P, in effect the intersecting bars 12 (or 11) are carried out from the outermost bar 11 (or 12) in equal length projections 12a (or 11a), by an amount corresponding to the normal spacing between the sides of adjacent bars, the end of each such projection being downwardly inwardly sloped corresponding to the bar side slopes; so that when one module is brought with its projecting bar side against the lugged straight side of an adjacent module, alternating feet can be received down in and interlock with respective lugs, with the bar projections of one module aligned with the correspondingly oriented bars of the adjacent module and also extending close to the edge bar of the adjacent module as seen again in plan in FIG. 2, and in section in FIG. 3. The projections may be slightly shorter than the normal spacing between opposed faces or sides of adjacent bars affording clearance for convenience in molding and laying. In effect the square outline of a module P is defined by the ends of the projections (i.e., a line or vertical plane tangent to the ends of the projections) in each of two sides, and by the respective bars at the other two sides.

As may be seen more clearly from FIGS. 4 and 5, each lug 15 has structure symmetrical about the longitudinal centerline of the respective grid bar and in plan expands into an end-rounded blunt barb-shaped enlargement. The foot receiving aperture or hole 16 may be considered to be in effect a basic foot receiving round hole intersected by broad radial slots at a right angle to each other, resulting in a half round portion 16a toward the lug tip, and two broad generally rectangular radial parts 16b in effect intersecting each other at a right angle with centerlines at 45 to the lug center line, and also intersecting the axis of the basic hole, or center of the half round.

A small lug foot 27, with bottom terminating coplanarly with the module feet 14, is located beneath the angular region between slots 16b for operative support of the lug as later described. Further two upward grip projections or posts 28 are provided on the lug regions forming the narrow end walls 29 for the slots 16b. Though the rectangular openings represented by said radial parts 16b each accommodate for desirable production tooling purposes a mold portion cooperating in defining the cavity region producing respective posts 28, resultant product lug structure in this area is functionally advantageous as later noted.

Each post 28 has a semi-cylindrical portion extending above and away from the slot end, which toward the slot merges into a vertical rib, e.g., triangular in cross section, carried down onto the slot end wall; the top or head part of the post being rounded, yet in plan of teardrop aspect; with the tailing of the drop projecting toward, and on the centerline of the slots; and presenting in plan an included right angle. The tailing enlargement of each head is comprised in effect of two intersecting semicylindrical portions, having intersecting horizontal axes, disposed respectively parallel and perpendicular to the lug centerline, therefore to the re-' spective bar centerline.

The shaping and spacing of the posts 28 with respect to each other across, i.e., on opposite sides of, the lug and with respect to the half-round hole surface 16a, are such that when another module is interlocked with a foot 14 received in hole 16, first the associated grid bar end extension of the entering foot elastically displaces from each other, and then seats between, the posts. At the same time the posts are being displaced in a common direction by the bar of the descending module carrying the entering foot. Thus each post is simultaneously subjected to two forces at right angles to each other, one tending to displace it away from the lug centerline, the other to move it parallel to the centerline, with resultant force or motion, for the given geometry, at 45 to the lug centerline and radially away from the axis of the half-round hole region.

Hence the slots 16b are directed as previously described, each thus forming an end wall 29, somewhat longer (i.e., slot wider) than the respective post 28, and extending perpendicularly to the resultant motion direction, affording in effect as a post pivot structure a region adapted to flex, thus distributing the stress arising upon insertion of a lug-received foot and bars. The lug foot 27 affords extra support to withstand the attendant downward thrust, in other words, also to provide the necessary force reaction for this purpose. By the inward bottom rounding of the inwardly carried surfaces 28c, there is provided clearance for the bottom margin or edge of the engage sloping bar side or bar end sides. with which the post makes a line contact well above the bottom edge of the side, as seen by reference to the dot-dash outline of a bar cross section appearing in FIG. 5.

The like ramp elements R are here shown in a form intended for the preferred manner of laying the array of primary modules to terminate in a row of projecting lugs across the vehicle opening or door of the garage, for convenience of installation operations as will appear.

Each ramp element R integrally comprises at least two longitudinal bars 21, in length equalling a full side dimension of a primary module; intersecting shorter like transverse bars 22, providing one longitudinal ramp side with the typical projecting ends 22a as described for 11a, and 12a, and the other longitudinal side ramp projections 22c; and feet 24 and 24b. The feet 24 at the long bar from which 22a project are identical to feet 14 to serve interlock functions. Preferably one end of the ramp module has a straight edge with :1 lug at the end of the inner long bar, with the two long bars projecting beyond the short bar 22 at the opposite end.

It is to be understood that the manner of interlock between primary modules and between ramp and primary modules is that shown in FIG. 2 and especially in FIG. 3, and described relative to FIGS. 4-5.

To confer a degree of added flexibility on each primary module, certain bars in each of the two perpendicular grid bar sets have centered longitudinal narrow deep bottom slots or grooves 25, each groove also extended through the several feet on that bar. For example, in a 12 bar by 12 bar" module, the fifth and ninth Advantageously first this grooving allows a module to flex under loading to accommodate to unevenness of the underlying concrete or other support surface, distributing the local loading force thereby to minimize module breakage; and also under similar conditions by the flexing to diminish force reaching the resilient gripping engagement of the lug grip posts and gripped elements, thus contributing to the working efficacy of the interlock.

The illustrated module P has the interlock lugs along adjacent sides, an arrangement by far preferred to disposition on parallel sides. For in installation, a first module P (full size or cut) can be layed at the corner of the area to be covered, oriented with the lugged sides disposed toward the interior of the area, so that when a first column is then built up by successively adding like oriented modules with feet of a projectionedged side of each engaged in a lugged side of the preceding module, the side of the completed first column toward the area interior-presents a line oflugs from all the modules in the first column, wherein are readily engaged the feet of the parallel projection-edged module sides along the length of the next laid column as it is similarly built up.

With the modules here shown, where one dimension or the other of the garage or floor space to be covered is not an even multiple of module lengths, and cutting is desired for a row or column, the plastic modules are readily cut, for example with an ordinary saw or hacksaw, transversely through the ribs along a line or plane passing through the apertures, thereby avoiding the necessity of cutting through the length of the rib, as would generally be required for such purposes by certain prior structure, while yet obtaining a good fill of the area.

Furthermore, if for some reason or another, cut modules might be desired in the midstof the array, such cutting may be so done that the lugged edges are retained on the module pieces to be installed, and further with the cuts made close to, or along the sloping side surface of, the adjacent bar portions of the parts to be removed; the interlock function is not destroyed; and an appearance of pattern continuation is obtained with little if any noteworthy difference from the general pattern.

In addition to providing the through-drainage aperture configuration above noted, the described structure provides modules readily molded with low cost tooling, from plastic materials, e.g., Duponts Delrin, or many other synthetic plastics of appropriate properties now available. Further to this end, it is to be understood that the feet may diverge from strict cylindrical form to have a slight taper as required for mold draft and easy release of elements from molds. Similar considerations may apply to other regions in accordance with known tooling and molded part designing considerations.

What is claimed is:

1. In a square integrally-formed molded plastic module adapted for laying interlocked with adjacent like modules in an array on a substantially flat and horizontal supporting surface, wherein a flat plate-like body has a multiplicity of apertures through the thickness of the body as through-drainage openings, integral equilength feet projecting from the bottom for support of the plate spaced from the support surface to provide under-drainage spaces, the improvement comprising:

on a first side margin of the module a row of equally spaced short free-ended bar-like projections extending perpendicularly from a margin-adjacent a first straight portion of the body; certain of said feet being each located on said straight portion at a respective region of intersection by a said projection; along a second straight portion of the body at a second side margin, a row of equi-spaced like laterally projecting interlock lugs, having spacings equal to multiples of the spacing of said projections, each lug downwardly offset from the plate top to extend under a like adjacent module and having a vertical aperture adapted to receive therein from above a foot on a said first side of a like adjacent module; each lug having a pair of upwardly extending grip posts thereon inboard of said aperture thereof and adapted in shape and spacing to be resiliently displaced by and to receive and grip therebetween a top-entering respective projection of an adjacent module having a foot entering from above, and to be engaged in, the aperture of said lug. 2. The improvement described in claim 1, wherein: said posts of a lug are adapted also to engage jointly and laterally a said first straight portion of an adjacent interlocked module cooperatively with the foot and lug engagement. 3. The improvement as describedin claim 1, wherein: projections as described are provided on two adjacent sides of the module, and lugs with posts as described are provided on the other two adjacent sides. 4. The improvement as described in claim 1, wherein: each said lug is provided with a break-off weakening or cut-off guiding groove at its region of joining to the rest of the module. 5. The improvement as described in claim 1, wherein: the cross section of said projections has equally sloped upwardly convergent sides, and the said first straight portion has a correspondingly sloped outer side from which the respective row of projections extend. 6. The improvement as described in claim 5, wherein: the said second straight portion has an outer side sloping upwardly back from the lugs thereon, the said projections terminate in end faces substantially complementary to the disposition of the last said outer side, whereby with a second module laid in alignment with a set of its projections toward a lug-bearing straight portion of the first module, projections substantially span the distance from one to another of adjacent straight portions of interlocked modules. 7. The improvement as described in claim 5, wherein: each of said posts has a head formation affording a clearance therebelow for lower sloped portions of said straight portions, said posts being so located that each head portion engages upper sloped portions of a projection engaged. therebetween and of a respective adjacent post of a straight portion from which the projection extends. 8. The improvement as described in claim 7, wherein: each said lug has an integrally molded ancillary foot formation beneath the region of the posts thereon. affording additional support to the lug under forces developed by entry of a projection between the posts.

said plate-like body has at least one bottom groove extending across a continuum of body material reaching substantially across the full plate width, said groove being parallel to a margin bearing said projections,

whereby said body may flex at said groove thereby to relieve tilting loading forces tending to disengage interlocked portions of modules. 

1. In a square integrally-formed molded plastic module adapted for laying interlocked with adjacent like modules in an array on a substantially flat and horizontal supporting surface, wherein a flat plate-like body has a multiplicity of apertures through the thickness of the body as through-drainage openings, integral equi-length feet projecting from the bottom for support of the plate spaced from the support surface to provide under-drainage spaces, the improvement comprising: on a first side margin of the module a row of equally spaced short free-ended bar-like projections extending perpendicularly from a margin-adjacent a first straight portion of the body; certain of said feet being each located on said straight portion at a respective region of intersection by a said projection; along a second straight portion of the body at a second side margin, a row of equi-spaced like laterally projecting interlock lugs, having spacings equal to multiples of the spacing of said projections, each lug downwardly offset from the plate top to extend under a like adjacent module and having a vertical aperture adapted to receive therein from above a foot on a said first side of a like adjacent module; each lug having a pair of upwardly extending grip posts thereon inboard of said aperture thereof and adapted in shape and spacing to be resiliently displaced by and to receive and grip therebetween a top-entering respective projection of an adjacent module having a foot entering from above, and to be engaged in, the aperture of said lug.
 2. The improvement described in claim 1, wherein: said posts of a lug are adapted also to engage jointly and laterally a said first straight portion of an adjacent interlocked module cooperatively with the foot and luG engagement.
 3. The improvement as described in claim 1, wherein: projections as described are provided on two adjacent sides of the module, and lugs with posts as described are provided on the other two adjacent sides.
 4. The improvement as described in claim 1, wherein: each said lug is provided with a break-off weakening or cut-off guiding groove at its region of joining to the rest of the module.
 5. The improvement as described in claim 1, wherein: the cross section of said projections has equally sloped upwardly convergent sides, and the said first straight portion has a correspondingly sloped outer side from which the respective row of projections extend.
 6. The improvement as described in claim 5, wherein: the said second straight portion has an outer side sloping upwardly back from the lugs thereon, the said projections terminate in end faces substantially complementary to the disposition of the last said outer side, whereby with a second module laid in alignment with a set of its projections toward a lug-bearing straight portion of the first module, projections substantially span the distance from one to another of adjacent straight portions of interlocked modules.
 7. The improvement as described in claim 5, wherein: each of said posts has a head formation affording a clearance therebelow for lower sloped portions of said straight portions, said posts being so located that each head portion engages upper sloped portions of a projection engaged therebetween and of a respective adjacent post of a straight portion from which the projection extends.
 8. The improvement as described in claim 7, wherein: each said lug has an integrally molded ancillary foot formation beneath the region of the posts thereon, affording additional support to the lug under forces developed by entry of a projection between the posts.
 9. The improvement as described in claim 7, wherein: in each lug the aperture is provided in an outboard-end enlargement; said aperture having an outermost arcuate portion complementary to a rounded inward surface provided on lug receivable feet, and two slot-like aperture extensions running inward to the base of respective posts.
 10. The improvement as described in claim 1, wherein: said plate-like body has at least one bottom groove extending across a continuum of body material reaching substantially across the full plate width, said groove being parallel to a margin bearing said projections, whereby said body may flex at said groove thereby to relieve tilting loading forces tending to disengage interlocked portions of modules. 